Sumif Unique

I am having a bit of trouble with trying to sum only unique values of an array.

1-1 8.00000
1-2 14.00000
1-3 19.00000
2-1 2.00000
2-1 2.00000

Since 1-1, 1-2 and 1-3 are all unique. I want to add that into the total along with ONE of 2-1.
The total should be 43.

I am able to do sumif and frequency for specific lines, but I have a big list and will be constantly changing..
Much appreciated if anyone can help me out.